This disclosure generally relates to polycarbonate lenses, and more particularly, to copolycarbonate lenses, methods of manufacture, and uses thereof.
Polycarbonates are useful in the manufacture of articles and components for a wide range of applications, from automotive parts to electronic appliances. Because of their beneficial properties such as transparency and impact resistance, polycarbonates have been used in applications such as camera lenses, eyeglass and safety glass lenses, illumination lenses such as light fixtures, flashlight and lantern lenses, and motor vehicle headlight lenses and covers. Since many of the lenses are used in high-temperature environment or have to be processed under abusive conditions, it is desirable for the lenses materials to have the ability to withstand elevated temperatures without deformation or discoloration, and/or ability to maintain good optical properties even when processed under abusive conditions.
Some known “high heat” copolycarbonates can have high glass transition temperatures of 150° C. or higher. But such polycarbonates are typically more yellow after processing and have lower transmission values. There accordingly remains a need for polycarbonate lenses having improved balance of high heat performance and optical properties.